28 lines
599 B
Java
28 lines
599 B
Java
// typeinfo/InterfaceViolation.java
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// (c)2017 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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// Sneaking around an interface
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import typeinfo.interfacea.*;
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class B implements A {
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public void f() {}
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public void g() {}
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}
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public class InterfaceViolation {
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public static void main(String[] args) {
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A a = new B();
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a.f();
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// a.g(); // Compile error
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System.out.println(a.getClass().getName());
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if(a instanceof B) {
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B b = (B)a;
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b.g();
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}
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}
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}
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/* Output:
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B
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*/
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